Gate length impact on plasma oscillations due to homojunctions in InGaAs FET/HEMT structures

Abstract

Theoretical investigation of the influence of gate length on the hybrid plasma frequencies caused by the presence of homojunctions is performed by means of hydrodynamic simulations. It is shown that when a homojunction approaches the gated channel region boundaries, a qualitative change of the spectrum of plasma excitations both in ungated and gated regions of the channel takes place. These changes can modify significantly the high-frequency regions of spectra of both admittance/impedance and current/voltage noise at the structure terminals.